Bill Ackman could hardly contain himself: American voters had just elected a businessman to run the country — someone who would steer the U.S. in the right direction.

While others were skittish about Donald Trump, Ackman felt nothing but optimism Wednesday morning when he heard the election results.

"I was extremely bullish on Trump, believe it or not," Ackman, the head of Pershing Square Management, said Thursday at the Dealbook conference in New York. "The U.S. is the greatest business in the world. It's been undermanaged for a very long period of time. We now have a businessman as president."

During the primary process, Ackman spearheaded an effort to draft another businessman — former New York mayor Michael Bloomberg — to run, but it wasn't to be. Ackman said Bloomberg was a better fit for him regarding social issues.

Absent his chosen candidate, Ackman said he was pleased with Trump, all things considered.

"My concern about Donald Trump is volatility. My concern was, who knows what he's going to do," Ackman said. "The guy just became president of the United States. This is going to be his legacy. Does he want to screw it up? No, he wants to be the greatest president this country has ever had."